According to a general usage pattern, image data recorded on an image sensing apparatus such as a digital camera or digital video camera are moved and saved in a large-capacity recording device (hard disk or the like) in a personal computer (to be referred to as a PC hereinafter) or saved in a random access medium like an optical disk such as a writable DVD or CD.
In this case, the user inserts a recording medium of the digital camera or digital video camera, e.g., a medium such as a compact flash memory, SD card, memory stick, or DVD, into the memory adapter of a PC, and transfers/records data onto a large-capacity recording device on the PC side. Alternatively, if the PC is not equipped with the above memory adapter, the PC is connected to the digital camera or digital video camera through a digital interface, e.g., a high-speed serial interface such as a USB or IEEE1394 interface, and data on the recording medium is read out on the PC side and transferred/recorded onto the large-capacity recording device. In either case, the user must designate and operate the transfer of data from the recording medium as a source to the large-capacity recording device by using an application on the PC.
FIG. 1 shows a state wherein a digital video camera 101 which uses a random access medium 102, e.g., a DVD media, as a recording medium is connected to a PC 103, to which a large-capacity, recording device 104 is connected, through a USB interface cable (obviously, both having USB interfaces).
The PC 103 operates as a USB host, and the digital video camera 101 operates as a USB device (slave). When the USB host is to acquire data from the USB device through the USB interface, communication is generally performed in accordance with standards like “Universal Serial Bus Still Image Capture Device Definition Revision 1.0 Jul. 11, 2000 (to be referred to as PTP hereinafter) or “Universal Serial Bus Mass Storage Class Bulk-Only Transport Revision 1.0 Sep. 31, 1999 (to be referred to as Mass Storage hereinafter).
In the case shown in FIG. 1, assume that communication is performed in conformity with the latter, i.e., Mass Storage.
Upon detecting the connection of the digital video camera 101 through a USB interface cable 105, the PC 103 acquires descriptor information from the digital video camera 101, and discriminates device information and a communication method, thereby recognizing that the digital video camera 101 is a mass storage class device. Thereafter, data are acquired in accordance with Mass Storage. In this case, the user can execute subsequent operation by operating an application on the PC 103.
FIG. 2 shows an example of the above application. This application is designed to read out data from an external device and record/save the data in an arbitrary recording medium. The user needs to activate a data save application 201 upon connecting the digital video camera 101 to the PC 103. In this application, a list of video data recorded on a recording medium of the digital video camera 101 is displayed in a display area 203, and a title bar (202) indicates that these data are located in the recording medium of the digital video camera drive. A title bar 204 indicates a recording device as a recording destination. In this state, the recording destination is a large-capacity recording device 104. When the user clicks a copy button 206 on the application, desired data in the recording medium of the digital video camera is copied to a designated folder in the large-capacity recording device 104. After the completion of the operation, the copied result is displayed in a display area 205. This example, however, is for the sake of simplicity. An actual application generally has specifications that allow the user to display video data as a recording source in thumbnail form or select data to be recorded, and also allow the user to select another recording device, e.g., an optical disk recording device such as a CD-RW or DVD-RW in place of the large-capacity recording device 104.
When the copy button 206 is actually clicked, the data save application 201 accesses the USB driver and mass storage driver of the PC 103 to read out data and start reception in conformity with Mass Storage. An operation sequence in Mass Storage will be briefly described below. The PC 103 as a USB mass storage host transmits Command Block Wrapper (CBW) to the digital video camera 101 as a mass storage device. When the digital video camera 101 as a mass storage device transmits Command Status Wrapper (CSW) in response to the received CBW, mutual communication is established. CBW and CSW only indicate a request and a response. Actual specific contents are designated by Command Block contained in CBW.
This Command Block is discriminated in accordance with the access interface of the device-side recording medium, such as:    “Advanced Technology Attachment Packet Interface for CD-ROMs.SFF-8020i”,    “Reduced block Commands (RBC), T10/1240-D”,    “Multi-Media Command Set2 (MMC-2)”, or    “SCSI Primary Commands-2 (SPC-2), Revision 3 or later”, and a command set to be used at the time of the establishment of communication with a USB mass storage host is determined by a code called a mass storage subclass.
In this case, Command Block is generated in accordance with an ATAPI (above-described “Multi-Media Command Set 2 (MMC02)” to be uniformly referred to as ATAPI hereinafter) command set (subclass 0x02). The PC 103 uses Command Block (READ(10)) for readout operation shown in FIG. 3 to read out data from the digital video camera 101, and reads out all data from the recording medium 102 of the digital video camera 101. Refer to the above ATAPI standards, for the detailed specifications of the READ(10) command in FIG. 3. A detailed description of this command will be omitted. The user need not be aware of these communication schemes, and can record/save data by operating an application 210.
In addition, a conventional technique of copying video data recorded by the digital video camera 101 onto a hard disk device connected to the video camera through IEEE 1394 has already been available (for example, Japanese Patent Laid-Open No. 2004-56396). This reference discloses an arrangement for selectively copying video data by remote control operation on the hard disk device side. An arrangement which allows data, having undergone copying to be erased is also disclosed.
In order to transfer and save data recorded on the recording medium 102 of the digital video camera 101 onto the large-capacity recording device 104 of the PC 103 by the above sequence, the user must operate the data save application 201. Although the above case has exemplified the simple application, complicated operation is required in practice. It is therefore cumbersome for a user who does not often use the PC 103 to operate the application.
A similar problem arises in patent reference 1. That is, the user needs to connect a video camera to a hard disk device and further operate copying operation sequentially by remote commander.
According to a general usage pattern of the digital video camera 101, after all video data or still image data obtained by photography are transferred/saved onto another large-capacity recording medium, the data recorded on the recording medium 102 of the digital video camera 101 are erased to prepare for new photographing operation. In consideration of these points, when data recorded on the recording medium 102 is to be transferred to another large-capacity recording medium, it is preferable to have as simple operability as possible and reliability that allows the user to visually recognize normal completion of transferring/recording/saving operation. That is, it is desirable for the user to simplify operation on the PC 103 as much as possible and perform control that can transfer/record/save all the data recorded on the recording medium 102 onto the large-capacity recording device 104 by only controlling the digital video camera (101).